In the fruit trade, and to a lesser extent in the vegetable trade, a present trend consists in placing a small adhesive label thereon in preparation for subsequent sale, the label mentioning, for example, the variety of the fruit, its country or region of origin, or else a trademark.
This applies in particular to selling apples.
Until now, to label apples automatically, wide use has been made of labelling machines sold by the firm SINCLAIR. A labelling machine of this type is described in Document EP-A-0 113 256 and the content thereof is considered as forming an integral portion of the present application.
Such a labelling machine essentially comprises a reel having a strip of label-supporting material wound thereon. It also includes means suitable for unsticking the labels one by one and transferring them to a labelling head. The labelling head is rotary and includes a plurality of elastically deformable studs in the form of a bellows through which suction can be applied. When a label is unstuck from the supporting material, it is taken so that its non-adhesive side is pressed against a stud which is under suction. When the stud comes over a fruit to be labelled, suction is interrupted and the label sticks on the fruit.
It has become the practice to label apples before they are sorted as a function of color, appearance, or size. After sorting, the apples are packaged, generally by being placed on trays having indentations which are then placed in cardboard packing cases.
One method of labelling consists in causing the apples to pass onto an endless conveyor belt prior to being sorted, with there being elements disposed on the belt suitable for organizing the flow of fruit into a series of parallel rows. A labelling machine of the above-specified type is provided for each row, and is itself secured to the framework of the conveyor belt.
That method of proceeding presents several drawbacks.
Firstly, all of the fruit are labelled even though some of them, e.g. damaged fruit, will not complete the usual sequence of packaging and sale, and as a result have no need to be labelled.
Secondly, when the fruit come under the labelling machines, they are disposed in entirely random orientations. Consequently, about 30% of the labels are badly placed, e.g. on the stalk of an apple, from which they quickly become unstuck, prior to packaging.